Hollow chitosan nanocomposite as drug carrier system for controlled delivery of ramipril

Abstract

Hollow biodegradable polymer nanoparticles as drug carrier possess effective low density and higher surface area. Chitosan hollow nanospheres were prepared using poly-D,L-lactide-co-glycolide as template by single emulsion method. The DLS studies showed increase in size from 125 nm to 186 nm for the formation of core@shell structure. The BET surface area increased from 62 m2 g−1 for chitosan@poly-D,L-lactide-co-glycolide to 111 m2 g−1 for hollow chitosan nanospheres. TEM analyses indicated core@shell, chitosan@poly-D,L-lactide-co-glycolide and the hollow morphology of the chitosan nanospheres. Ramipril in acetone (1.5 mg/mL, 3 mg/mL and 5 mg/mL) was physically adsorbed onto hollow chitosan nanospheres and the amount of adsorbed ramipril was determined by HPLC. Higher entrapment efficiency (91%) with 96% of the drug content was observed for the sample with 5 mg/mL of the drug. The in-vitro release of ramipril of 86% and 73% was achieved in acetate (pH-3.3) and phosphate (pH-6.3) buffers respectively while only 48% of ramipril in Tris buffer (pH-8.0) medium. Korsemeyer-Peppas model of drug release indicated the release of ramipril being swelling controlled.